Electrically operated time lapse traffic signal



Dec.'6, 1949 J. s; ELAM 2,490,585

ELECTRICALLY OPERATED TIME LAPSE TRAFFIC SIGNAL Filed Feb. 16, 1946 .5 She'ets-Sheet '1 A TTOE/VE Y Dec. 6, 1949 J. s. ELAM 2,490,585

ELECTRICALLY OPERATED TIME LAPSE TRAFFIC SIGNAL Filed Feb. 16, 1946 3 Sheets-Sheet 2 I /J J5 24 Z4 A 7'7'ORNE Y Dec. 6, 1949 J. s. ELAM 2,490,585

ELECTRICALLY OPERATED TIME LAPSE TRAFFIC SIGNAL Filed Feb. 16,1946 3 Sheets-Sheet 3 50 87 a6 98 5 7 29 via 6 LINE 90 49 Patented Dec. 6, 1949 ELECTRICALLY OPERATED TIME LAPSE TRAFFIC SIGNAL Jay S. Elam, Huntington Park, Calif.

Application February 16, 1946, Serial No. 648,028

7 Claims.

This invention relates to traffic signals and has for its primary object to provide a novel and improved signal structure affording both motorists and pedestrians a better visual conception of the time relationship of the Go and Stop periods. 7

Another object of the present invention is to provide a trafiic signal embodying illuminated "Go and Stop areas and provided with pointer or index means sweeping said areas whereby both motorists and pedestrians can visualize that portion of the Go or Stop period that remains before a signaling change becomes efiective.

Another object of the invention is to provide a trafiic signal of the character referred to which embodies novel means for illuminating pointer or index means for improved visibility.

Another object of the invention is to provide a trafic signal incorporating novel and improved means for moving or driving an index means for the type referred to at two difierent rates of speed so that trafiic in one direction may have a longer Go period than traffic in the other direction.

A further object of the invention is to provide a traflic signal embodying novel means eiiecting the change from a Go period at one-rate of speed to a Go period at a different rate of speed whereby traffic at an intersection can be controlled in accordance with the volume of trafiic moving along respective directions through the intersection.

A further object of the invention is to provide a traiiic signal embodying novel means, when the signaling period is suspended, for automatically bringing the index means to a neutral position with respect to the Go and Stop areas of the signal.

A still further object of the invention is to provide a traflie signal embodying blinker signals which become automatically effective as warnings to motorists and pedestrians when the operation of the index controlled signal is suspended.

-A still further object of the invention is to provide a trafiic signal capable of being designed as a multi-face structure controlling three, four, five or more point intersections, and adapted for suspension at the center of such intersections or to be mounted on corner posts, as desired.

My invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceabillty.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawings merely show and the following description merely describes one embodiment of the present invention, which is given by way of illustration or example only.

In the drawings, like reference characters designate similar parts in the several views.

Fig. l is a broken partial elevational, partial sectional view of a traflic signal constructed in accordance with the present invention.

Fig. 2 is a plan view thereof on a reduced scale.

Fig. 3 is a plan sectional view thereof.

Fig. 4 is a side view of a signal unit employed in the invention.

Fig. 5 is a rear view thereof.

Fig. 6 is a wiring diagram showing the manner of controlling the various lamps and the index pointers of the traffic signal in Fig. 1.

The traflic signal which is shown in the drawing comprises a four-sided structure for controlling a four point intersection. The signal comprises, generally, a housing [0 having aligned openings II and I2, and aligned transverse openings l3 and I4; identical signal units l5 mounted in each opening embodying a Go area [6. a Stop area H, a Caution area I, and an index or pointer l9 mounted to sweep said areas in the manner of a clock hand; a pair of electric motors 20 and 2| mounted in the housing; reduction gearing 22 driven by said motors; means 23 driven by the reduction gearing for driving the pointers l9 through drive shafts 24 and gearing 25 within each unit 15; means 26 for illuminating the Go, Stop and Caution areas of each unit I5; means 21 for illuminating the pointers l9; commutator means 28 for controlling the motors 20 and 2i and the illuminating means 26; commutator means 29 for bringing the motors to a position whereby the pointers are brought to rest at a neutral position with respect to the area l6, l1 and 18 or the units It; electric means 3 3&3 controlling the latter; and blinker means 8| operatively effective upon suspension of operation of the traffic signal.

The housing Hi comprises, essentially, similar intersecting tubes aifording the mentioned openings ii, l2, l3 and M, and a cylindrically tubular vertical housing part 32 extending from the interior of the housing downward through the bottom thereof to provide a depending cuff 33. The upper portion of the housing part 32 is provided with a base or platform 34 serving to support the motors 26 and and the reduction gearing 22. The cuff 3-3 is provided with the means 3| which comprises transversely aligned lenses or windows 35 through which are visible the light of a lamp 3E controlled by a blinker switch 31. A cover plate 33, for the bottom of the cuff, aifords access to the means 3! for servicing thereoi. The plate 38 serve to mount the housing upon a post, if desired. However, the housing shown is provided with a bracket 39 at the top thereof and formed with holes All whereby the housing can be suspended from an overhead wire. Access to the interior of the housing is afforded by a removable plate M at the top, as shown, or otherwise suitably located.

Each unit I5 o p is s a frame desi ned to smig y fit the respective openings H, I2, [3 and i i, a shell 63 carried by the frame 42 and serving as a housing for the illuminating means 26, a

transparent front closure window 44., and a centrally disposed preferably cast unit. 45 carried by the shell and ser ing to carry the pointer 19, the gearing 2 5 and the illuminating means 21. E ach unit it further includes a light passing green Gopanel 4.5, red Stop panel 41, and an amber Caution panel 48. The panels 46, a? and id are suitably proportioned and are held in place by a frame 4911 which defines the panels.

The mentioned areas Iii, I! and 18 are formed by the respective panels 65, 41 and 48 as they are seen through the transparent window 44. It will be later seen that the lamps 49, 5B and 5| mounted in each unit l5 illuminate the areas [6, l1 and i8; in synchronous relation with the movement of the pointer I9.

Each pointer i9 is formed of a light piping material, such as Lucite and comprises an arm 52 formed with a hub 53. mounted at the center of; the casting as. The hub is so positioned as to receive the light. from the means 21 and to direct the same along and throughout the length of the arm 52. In order to give the pointer luminosity, it. is provided with a sloping front face 54 wherebylight is projected forward according to the properties of Lucite. The rear face 55 of the pointer is. rendered opaque so as not to pass light from the illuminating means 26. Located between the Window 4.4 and the panels 46, 41 and 4B, the illuminated pointeris readily visible.

The hub 53 of the pointer 19 is mounted in a sleeve Eli which in turn is carried by the casting 45 by means of anti-friction bearings 51. The gearing 25 comprises a bevel gear 58 on the sleeve 56, a bevel pinion '59 in mesh therewith, a bevel gear 6% mounted with the pinion 59, and a bevel pinion 6] in mesh with'the gear 60. The pinion 6! is carried by a shaft stud 62 extending from the unit 15 inwardly toward the interior ofthe housing It). The gearing arrangement is such that the speed of rotation of the pointer I9 is considerably less than that of the shaft stud E2. The outwardly extending end of said shaft stud is providedwith coupling element 63. The pointer illuminating means 21 comprises a lam 64 car- 4 ried by the casting 45 and provided with a suitable reflector for directing its light toward and through the pointer hub 53.

The motors 20 and 2! are essentially similar and may operate at similar or at diifcrent speeds. In the present instance, the motors are mounted on the under side of the platform 34 to project into the housing part 32. The motor 20 is provided with a drive pinion 65 on the end of its armature shaft. Similarly, the motor 21 is provided with a smaller drive pinion 6B.

The reduction gearing 22 mounted on the upper side of the platform 34, is driven by said pinions 65 and GB. Depending on which motor is in operation, said gearing is driven at different rates of speed. A suitable support 51 is provided for the reduction gearing which comprises a relatively large gear 63 engaged by both pinions 65 and 68, and one or more pairs of reducing gears 69 which effect a drive from the gear 68 to a bevel gear 10. With the motors 29 and 2| operating at the same speed, it will be evident that the motor 20 will drive the bevel gear 16 faster than will the motor 21. When one motor is in operation, the armature shaft of the other is merely idling as driven by the gear 68. From the foregoing it. will be seen that the relatively high speeds of the motors 20 and 2| result in two low but difierent speeds of rotation of the bevel gear E0.

The means 23 includes the bevel gear in and a plurality of bevel pinions "H in mesh therewith. For the fouresided signal shown, four bevel pinions are provided for driving the shafts 24. Each shaft 24 is provided with a coupling element- 12 1 fordriving connection with the respective coupling elements 63.01 the units 15.

The means '28 is employed for controlling the motors 20 and 2! and comprises an electric commutator mounted on one of the shafts 24. The commutator comprises a drum 13 having a complete band M and two partial bands or segments 15 and 16 suitably proportioned to provide a (30" period for one direction of trafilc of either the same or a shorter period than for the other direction. For Go periods of the same length, the segments 15 and 1-6 would be of equal length, i. e., substantially semi-circular. For Go periods of different lengths, one segment would be longer than the other in a related proportion to the difference in the lengths of the *Go periods. The band M and segments i5 and 16 are provided with contacts T1, '18 and 19, respectively; Each segment and It is electrically connected to the band M, as seen in the diagram of Fig. 6'.

The commutator means 29 comprises a drum, 80. on another of the shafts 24. This commutator comprises a complete band BI and a partial band or segment 82. The latter has only a, small gap of some 5 of its circumference. The hand 81' is. provided with a contact 83 and the segment 82 with a contact 84. The band 8! and segment 82 are electrically connected as shown,

The means 30 comprises an electromagnetic switch having a coil 85, an armature 86. controlled thereby and contacts 8-1 and 88 engageable by the armature.

One manner of electrically connecting the motors 2-0 and 21, the lamps 49, 50 and 5t, the, commutators 28 and 29 and the means 30 is shown in Fig. 6. The Go lamps 9 Qr opposed, and aligned directions of control of the signal are connected with the Stop" lamps 50 and the, Caution lamps 5| for the transverse directlens of control of the signal. Assuming the signal to be oriented to an east-west and a north-south thoroughfare intersection, a common connection is made across the circuit of one motor as of the east and west "Go" lamps 49 and the north and south "Stop lamps 59 and Caution lamps SI, and a common connection is made across the circuit of the other motor 2| of the north and south "Go? lamps 49 and the east and west "Stop lamps 5n and Caution lamps 5|.

A time controlled or otherwise controlled switch 89 may be incorporated in the signal or otherwise disposed for controlling the signal. With the switch 89 closed, the coil 85 is in electric circuit to cause the armature to engage contact 81. The current will then flow from the line through conductor 98, armature 86, conductors 9| and 92, contact 11, band 14, that segment 15 or 16 which is engaged with its contact 18 or 79, respectively, in this case, segment 16 and contact 19,, conductor 93, motor 2|, and conductor 94 which is the other leg of the electric line, The circuit thus established will operate motor 2| to drive all of the pointers l9 at a one rate of speed. A parallel connection across the motor 2| is made by conductors 95 to the north and south Go lamps and east and west Stop and Caution lamps. These lamps will be lighted during operation of motor 2|. The various pointers |9 are oriented so that the north and south pointers are sweeping or traversing the Go areas as the east and west pointers are traversing first the Caution and then the Stop areas.

As the commutator 28 is rotated by the motor 2|, the segment 16 will leave contact 19 and segment 15 will engage contact 18. The circuit through motor 2| will be broken and the current will now flow from band 14, segment 15, contact 18, conductor 96 and motor 20 to line conductor 94 to cause a drive of the pointers |9 at a different rate of speed. A parallel connection across the motor 29 is made by conductors 91 to the east and west Go lamps and the north and south Stop and Caution lamps. These latter lamps will be lighted during operation of motor 29. The signal will continue to operate with the motors 20 and 2| alternatively driving the pointers l9.

When current to the coil 85 is interrupted by opening of the switch 89, said coil will release the armature 86 which will engage contact 88. The commutator 29 will now be placed in the circuit between conductors 98 and 92. The current will flow from conductor 98, armature 86, contact 88, conductor 98, contact 84, segment 82, band 8|, contact 83, and conductor 99 to conductor 92. Whichever motor 29 or 2| is in circuit will con tinue to operate until the gap in segment 82 registers with contact 84 when the circuit is broken to the motors and the lamps of the signal. By synchronizing the position of the gap in the segment 82, with the positions of the pointers 9, the latter come to rest in a neutral position. One pair of aligned pointers will come to rest in front of the Caution areas of opposed signal faces and the other pair will come to rest at the division between the Go and Stop areas. In this manner confusion to motorists and pedestrians is obviated.

When the switch 89 is again closed, the operation as above outlined will be established. Upon opening of the switch 89, the blinker means 3| may be set into operation in a conventional manner.

The generally simple electrical circuit above outlined may be further simplified by using a low voltage single line grounded circuit wherein each lamp and motor is connected to a common electrical ground as, for instance, the signal housing. Modifications in the circuit may be incorporated. The switch 86 may be of the toggle make and break type, and the commutator means 28 may be designed to include additional segments for the caution lights 5| instead of their operation together with their respective stop lights 50. The pointer light 64, of course, is slim ply connected to remain lighted at all times except when the commutator means 29 opens the circuit.

While I have illustrated and described what I now regard as the preferred embodiment of my invention, the construction is, of course, subject to modifications without departing from the spirit and scope of my invention. I, therefore, do not wish to restrict myself to the particular form of construction illustrated and described, but desire to avail myself of all modifications that may fall within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A traffic signal comprising a plurality of similar units each having "Go and Stop areas facing in different directions, a pointer in each unit movable to traverse said areas, reduction gearing connected with said pointers, a relatively large gear connected with said reduction gearing, and a pair of motors included in an electric circuit, pinions on said motors and in mesh with said larger gears, said pinions having unequal diameters and arranged alternately to move all of said pointers at different rates of speed.

2. A traffic signal comprising a plurality of similar units each having Go and Stop areas facing in difierent directions, a pointer in each unit movable to traverse said areas, a pair of driving motors, mechanical connections including reduction gearing connected to said pointers, a large gear connected with said reduction gearing, diametrally unequal pinions on the motors in mesh with said large gear, and means effecting an automatic switch-over from one driving motor to the other to vary the speed of travel of said pointers.

3. A trafiic signal comprising a plurality of similar units each having Go and Stop areas facing in different directions, a pointer in each unit movable to traverse said area-s, a pair of driving motors having diametrally unequal pinions, a large gear in mesh with said pinions, mechanical connections including reduction gearing and said large gear connecting the pointers, and means efiecting an automatic switch-over from one driving motor to the other, said latter means comprising an electric commutator driven by said reduction gearing for varying the speed of traverse of said pointers.

4. In a trafiic signal, reduction gearing including a large gear, a pair of motors each having a diametrally unequal pinion in mesh with said large gear for alternately driving the reduction gearing at difierent rates of speed, a plurality of pointers driven by the reduction gearing an electric circuit including said motors, means controllable by said reduction gearing for automatically including one or the other of said motors in said circuit, and trafiic signaling areas associated with and traversed by said pointers, respectively.

5. A traffic signal comprising a housing having openings facing in different directions, a similar unit in each opening and having visual traflicdirecting areas, translucent pointer means traversing said areas of each unit and each said means having a mounting portion, means to illuminate said mounting portion and thereby render luminous each pointer means, and means for illuminating said areas each in synchrony with the movement of its associated pointer.

6. In a traflic signal, a pair of motors, an electric circuit for driving said motors alternately, a plurality of pointers driven alternately by each motor, a plurality of traflic-directing lights connected with each motor circuit, said lights bein illuminated only when the respective motor is operating reduction gearing between said motors and connected to said pointers, and means in said circuit alternately driven by said motors for alternately closing said electric circuits, said latter means comprising a pair of commutators having a common current conducting band and phased segments connected in each respective electric circuit.

7. A trafiic signal having Go and Stop areas facing in difierent directions, reduction gearing, pointers connected to said gearing, a pair of electric motors, an electric circuit including said motors and a switch, a large gear connected to said reduction gearing, diametrally unequal pinions on said motors in mesh with said large gear, and a pair of commutators on said reduction gearing governing the flow of current to one motor or the other to regulate the speed of travel of said reduction gearing and said pointers.

JAY S. ELAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,847,903 Schulbert Mar. 1, 1932 1,850,897 Shepherd Mar. 22, 1932 20 1,852,989 Walrath et a1. Apr. 5, 1932 1,905,378 Gechter Apr. 25, 1933 

